A group of rats is called a colony, a term that reflects real, well-documented social organization rather than just a random gathering.
Rats are among the most heavily studied mammals in behavioral science, and what researchers have found consistently surprises people: rats live in structured social groups with genuine cooperation, communication, and even documented empathetic behavior. The many nicknames for a rat group, from the almost affectionate “mischief” to the alarmed “plague,” say more about human attitudes toward rats than about the animals themselves.
What Is a Group of Rats Called?
The standard, most accurate term is a colony of rats, used especially in scientific and behavioral contexts. In everyday and older usage, though, you’ll also frequently see a mischief of rats, probably the best-known of the more colorful alternatives, and a pack of rats.
Other Collective Nouns for Rats
Rats’ long, uneasy relationship with humans has produced an unusually vivid set of collective nouns:
- Mischief — the most famous alternative, capturing rats’ reputation for cleverness and troublemaking.
- Pack — occasionally used, borrowed from group-hunting mammal terminology.
- Horde and Swarm — used for especially large rat populations, emphasizing scale over social structure.
- Plague — a historically loaded term for a large, infesting rat population, tied to rats’ long association with disease outbreaks in dense human settlements.
- Rabble — describes a loosely scattered, disorganized-looking group of rats.
- Kingdom — a more whimsical, half-joking term occasionally applied to a rat group.
Where Did the Name Come From?
“Colony” is the straightforwardly descriptive, scientifically grounded term: rats genuinely live in colonies with clear social hierarchies, shared burrow systems, and cooperative behavior, so the word reflects real biology rather than folklore.
Most of the more dramatic alternatives, “mischief,” “plague,” “horde,” reflect humans’ long and largely adversarial history with rats rather than any formal medieval hunting tradition. Rats have lived alongside, and often against, human settlements for millennia, and their reputation as disease carriers, most infamously linked (though the connection is more complicated than commonly believed) to outbreaks of plague in medieval Europe, shaped a vocabulary that leans heavily toward alarm and distaste rather than the more neutral or admiring terms used for animals like horses or deer.
Rat Facts
- Habitat: Rats, especially the widespread Norway rat and black rat, are found on every continent except Antarctica, thriving in both wild burrow systems and dense human settlements.
- Social behavior: Rats live in structured colonies with clear hierarchies. Laboratory research, since rats are among the most studied mammals in behavioral science, has documented genuinely sophisticated social behavior, including rats working to free a trapped companion with no direct reward for doing so.
- Diet: Rats are opportunistic omnivores, eating grains, fruit, meat, and human food waste, a major reason they thrive so successfully around people.
- Lifespan: Wild rats typically live only 1–2 years due to predation and disease, though rats kept in captivity can live 2–3 years or more.
- Reproduction: Rats reproduce quickly, with short gestation periods and large litters, a major factor in how fast wild colonies can grow when food and shelter are available.
- Burrowing: Wild rat colonies build extensive burrow systems with separate areas for nesting, food storage, and waste, broadly similar in complexity to rabbit warrens.
Example Sentences
- A colony of rats had established itself beneath the old barn.
- Neighbors complained about a mischief of rats living behind the restaurant.
- The exterminator was called after a rabble of rats was spotted in the alley.
Other Names for a Group of Rats
Explore the individual collective nouns for rats in more depth:
- A Colony of Rats
- A Horde of Rats
- A Kingdom of Rats
- A Mischief of Rats
- A Pack of Rats
- A Plague of Rats
- A Rabble of Rats
- A Swarm of Rats
Frequently Asked Questions
What is the most accurate term for a group of rats?
Colony is the standard, scientifically grounded term, reflecting rats’ genuine social structure and shared burrow systems.
Is rat social behavior actually as sophisticated as it sounds?
Yes. Laboratory research has documented rats displaying real cooperative and even empathetic behavior, including working to free a trapped companion with no direct reward.
Where does a mischief of rats come from?
It’s an old term reflecting rats’ longstanding reputation for cleverness and troublemaking rather than any single documented behavior.
Is a plague of rats connected to the historical Black Death?
The phrase reflects rats’ long association with disease in crowded human settlements, though modern research suggests the full picture of how plague actually spread historically is more complicated than rats alone.
What’s the difference between a colony and a swarm of rats?
Colony emphasizes social structure, while swarm and horde are more about sheer numbers: an especially large or overwhelming rat population.
Do mice have a similar collective noun?
Yes, a group of mice is often called a nest or, playfully, a mischief as well, terms that overlap because rats and mice are closely related rodents with similar social habits.
Related: Collective Nouns for Mammals